A 5A UK switched socket. Hard to say if it is meant to be mounted vertically or horizontally given the labelling. Of interest is the switch mechanism being a fast acting tumbler switch making this suitable for DC mains.
I've seen outlets similar to that in old homes mounted both ways. Although everybody expects 3-pin sockets to be mounted with the earth uppermost, the old 2-pin outlets could be found mounted any which way. Bearing in mind that these surface-mounted accessories were typically screwed to the "skirting board" (that's a baseboard -- not sure which term you use down under), it was often a case of mounting whichever way was more convenient.
D.C. mains were still being used in some older city areas well into the 1950s.
A triple adaptor rated at 5A also from the UK.
I have a box full of three-way adapters similar to that one, but just a slightly different molding. Three-ways with squared sides (so that the two side plugs are at 90 degrees to the front one) were also very common.
This looked like an oversize BC plug at first, but pulling the halves apart revealed a BC to 5A adaptor with captive two pin 5A plug. I'm curious to know why the short piece of string is there. I've got another of these adaptors and it's the same.
I have some of the BC-to-5A adapters, complete with the little hole on the side, although the string which once attached to it is long gone.
These adapters were very common at one time to run radios, clothes irons, and such things from a convenient light socket in the days when outlets around the house weren't so numerous. The tethered 5A plug and BC adapter came about as an accessory to enable a portable appliance to be used on either a 5A baseboard/wall outlet or a lamp socket.
I'd never seen one of these before. While you could use it to provide additional lighting in a room, a light bulb at floor level would look a bit odd. It's obviously intended to run appliances fitted with a BC plug from a UK round pin socket. What's of interest is the pins can swivel to accomodate different pin spacings.
Yes, while the BC-to-5A adapter was widely employed, often times an appliance which was plugged into a light socket regularly would be fitted with a BC plug. This adapter then solved the converse problem of when that device needed to be connected to a regular wall outlet. I have one which seems to be the exact same model as yours.
The pins will adjust to fit either a 2-pin 5A or the L/N pins of a 3-pin 5A socket. One of the peculiarities of BS546 was that the L/N pin spacing on the 3-pin versions was slightly different from that on the 2-pin outlets, so that a normal 2-pin 5A plug wouldn't fit a 3-pin socket (why they designed them that way, I have no idea).